Incinerator



Aug. 30, 1966 w. R. CRAWFORD ETAL INCINERATOR Original Filed June 20, 1958 2 Sheets-Sheet l g- 30, 1956 w. R. CRAWFORD ETAL 3,269,340

United States Patent 3,269,340 HNCHNERATOR William R. Crawford, Cincinnati, Ohio, and James W.

Lannert, St. Joseph, Mich, assignors to Whirlpool Corporation, a corporation of Delaware Original application June 20, 1958, Ser. No. 743,246, now Patent No. 3,104,629, dated Sept. 24, 1963. Divided and this application July 9, 1963, Ser. No. 293,674 4 Claims. (Ci. 110-8) This application is a division of our copending application Serial No. 743,246, filed June 20, 1958, now Patent No. 3,104,629, issued September 24, 1963.

This invention relates to incinerators and in particular to domestic incinerators for effecting combustion of material such as garbage.

In domestic incinerators, substantial elimination of smoke and odors is desirable. Further, as such incinerators are utilized by different persons having different technical abilities, a high degree of efficiency and simplicity of operation is desirable. Another problem that must be considered is that the domestic user may not maintain proper maintenance, such as necessary to provide proper air flow into and from the combustion chambers. The known domestic incinerators do not satisfactorily meet these needs.

The principal feature of the instant invention is the provision of a new and improved incinerator.

Another feature is the provision of such an incinerator having an improved afterburner means.

A further feature is the provision of such an incinerator wherein the afterburner is associated with a partial combustion chamber in a new and improved manner.

A still further feature is the provision of such an incinerator having new and improved air delivery means.

Yet another feature is the provision of such an incinerator having new and improved automatic adjustment means for effecting proper combustion of different types of material.

A still further feature is the provision of such an incinerator arranged for improved co-ordinated operation of the afterburner and partial combustion burner means for increased efiiciency in the operation thereof.

Other features and advantages of the invention will be apparent from the following description taken in connection with the accompanying drawings wherein:

FIGURE 1 is a vertical section, taken approximately along the line 11 of FIGURE 2, of an incinerator embodying the invention;

FIGURE 2 is a horizontal section thereof taken approximately along the line 22 of FIGURE 1; and

FIGURE 3 is a horizontal section thereof taken approximately along the line 3-3 of FIGURE 1.

In the exemplary embodiment of the invention, as shown in FIGURES 1 through 3 of the drawing, an incinerator comprises a first housing 11 defining an ignition chamber 12 in which an incomplete combustion of material to be incinerated, such as garbage 13, is effected. Directly above chamber 12 is a second housing 14 defining an afterburner chamber 15 arranged to receive the products of combustion from the ignition chamber for completion therein of the combustion of the products of combustion. The partial combustion of garbage 13 in ignition chamber 12 is effected by means of a first burner 16 extending across a lower open end 17 of housing 11. A second burner 18 is disposed within afterburner chamber 15 for providing additional heat energy to assure a completion of the combustion in the afterburner chamber 15.

Surrounding ignition chamber housing 11 and superposed afterburner housing 14 is an outer enclosure 19 R 3,269,340 Patented August 30, 1966 provided with a front wall 20 having an opening 21 for admitting garbage 13 to ignition chamber 12. Opening 21 is normally closed by means of a door 22 movably mounted on front wall 20. Below opening 21, front wall 20 is provided with a second opening 23 normally closed by a door 24 having a handle 24a. Opening 23 extends upwardly from bottom wall 25 of enclosure 19 and permits desired removal of ashes 26 resulting from the combustion of garbage 13 in ignition chamber 12. An ash pan 27 is removably disposed on bottom wall 25 below open end 17 of the ignition chamber housing to collect the ashes 26 and facilitate the disposing thereof. An ash compactor 27a may be provided to reduce the volume of ashes in pan 2'7 and, thus, permit a greater amount of ashes to be received therein before removal is required.

To support the desired combustion within ignition chamber 12 and afterburner chamber 15, accurately controlled volumes of air are delivered to each chamber. For this purpose, a plurality of air inlet openings 28 are provided in rear wall 29 of outer enclosure 19 adjacent upper wall 30 thereof. From openings 28, the air passes over and around the afterburner housing 14, thereby becoming preheated. A portion of this air is drawn into afterburner chamber 15 through a plurality of openings 31 in rear wall 32 of afterburner housing 14. The quantity of air so drawn through openings 31 and around burner 18 is a function of the draft and temperature in the afterburner chamber. The remainder of the air passes between ignition chamber housing 11 and outer enclosure 19 to enter the bottom of ignition chamber 12 through lower open end 17 of housing 11. To provide improved delivery of this air and flame from burner 16 to the different portions of the garbage within the ignition chamber, a wire basket structure 33 is provided therein to receive and effect a spacing of the garbage slightly inwardly of the walls of housing 11, thereby defining an air and flame flow space 34 laterally surround ing the garbage. The gaseous products of combustion pass upwardly from ignition chamber 12 into 'afterburner chamber 15 through an opening 35 in top Wall 36 of ignition chamber housing 11 adjacent the rear wall thereof. Thus, as the gaseous products of combustion enter the afterburner chamber 15, they are rnixed with an additional volume of air delivered thrugh openings 31 to permit the desired completion of the combustion thereof. The resultant purified effluent (having had substantially all smoke and odor removed therefrom in the afterburner chamber) is passed outwardly from the afterburner through an opening 37 in the upper wall 38 of housing 14 and a suitable outlet duct 39 extending from opening 37 through upper wall 30 of outer enclosure 19. Outlet duct 39 may be connected to a suitable stack as desired.

To regulate the draft of the effluent at the afterburner outlet, an Opening 40 (FIGURE 2) is provided in rear wall 32 of afterburner housing 14 and a damper 41 is disposed movably across opening 40 to vary the fair flow through the opening and into chamber 15 as a direct function of the draft suction at opening 37. Thus, should the combustion within incinerator 10 tend to run away such as might occur during incineration of readily combustible material, such as dry paper, damper 41 provides an automatic reduction of the draft through the incinerator.

The general construction of incinerator 10 having been described, the specific detailed structure thereof will now be considered. Housings 11 and 14, and outer enclosure 19 are preferably formed of a sheet metal such as sheet steel. Housing 11 is adapted to hold a substantial amount of garbage, permitting, for example, the use of the incinerator, in an ordinary domestic application, on a oncea-day schedule. However, because of the high efficiency of incinerator 10, the unit may be relatively small, a typical dimensioning of housing 11 being 2 feet wide by 2 feet deep by 4 feet high.

Wire basket 33 is preferably substantially rigid and may be comprised of inch diameter rods secured as by welding. Door 22 may be formed of sheet metal, such as sheet alloy steel, and is preferably pivotally secured at its lower end to enclosure front wall by a hinge 42. A handle 43 is provided on the upper end of the door 22 for manipulation of the door as desired. On the rear of door 22 is secure-d a chute 44 which guides the garbage through opening 21 and into ignition chamber 12. To facilitate the deposit of garbage, means are provided for retaining door 22 at approximately a 45 angle in the open position, such means being illustrated herein as comprising a clip 45 on chute 44 adapted to engage an overhanging ledge portion 46 of ignition chamber housing 11 when door 22 is thusly disposed.

As best seen in FIGURES 1 and 3, the lower end of ignition chamber housing 11 tapers so that lower open end 17 is restricted in area. Partially closing open end 17 to support garbage 13 in the ignition chamber is a grate 47 comprising a pair of fingered bars. A shaker mechanism 48 is associated with grate 47 to effect a shaking reciprocation thereof, when desired, thereby to cause ashes to pass downwardly through open end 17 and into ash pan 27. Burner 16 is disposed slightly below grate 47 and herein comprises a power burner producing approximately 12,000 B.t.u.s per hour.

Referring now more specifically to FIGURES 1 and 2, the improved afterburner means is seen to comprise a generally horizon-tally extending, circuitous passage defined by suitable baflle Walls within afterburner housing 14. Four such bafl'le walls are provided herein, each wall extending vertically from the underside of upper Wall 38 to the upper side of wall 36. A first 'baflle wall 49 is spaced from right side wall 50 of afterburner housing 14 approximately of the width of the afterburner chamber. Wall 49 extends forwardly from rear wall 32 of housing 14 to a short front wall portion 51 of the afterburner housing 14 offset rearwardly from the main front wall portion 52 thereof by an interconnecting horizontal wall 53. As best seen in FIGURE 1, walls '51 and 53 define, with the forward end of wall 36, a space 54 extending across the width of the afterburner housing, through a portion of which space extends burner 18.

A second baflle wall 55 is spaced approximately midway between right side wall 50 and left side wall 56 of housing 14 and extends rearwardly from the front wall thereof defined by portions 51, 52 and 53 slightly more than /2 the distance toward rear wall 32. A third bafile wall 57 is spaced approximately /4 of the width of the afterburner housing from left side wall 56 and extends rearwardly from front wall portion 51 to the front edge 58 of opening 35. The fourth baffle wall 59 is aligned with edge 58 and extends between third wall 57 and first wall 49. The lower rear corner of first baffle wall 49 is cut out overlying opening 35 (see FIGURE 1) to define a horizontal edge 60 and a vertical edge 61. Extending angularly upwardly from the junction of left side wall 56 with horizontal wall 36 to edge 60 is a wall 62 which deflects the products of combustion passing upwardly from ignition chamber 12 through opening 35 toward the space between first baflle wall 49 and right side wall 50. To preclude communication between the passage portion bounded by left side wall 56 and baffle wall 57 and the space under angular wall 62, wall 59,is provided with a projecting portion 63 extending across the opening therebetween. Thus, as best seen in FIG- URE 2, the flow passage of the efiluent through the afterburner chamber is upwardly from the entire opening 35, through the space between baffle wall 49 and right side Wall 50, past burner 18 which is disposed at one end of this space and is thus adjacent the inlet of the flow passage, into the space between wall 49 and wall 55 after making turn, into the space between wall 55 and 57 after making another 180 turn, into the space between wall 57 and side wall 56 after making another 180 turn, into the space between Wall 59 and rear wall 32 of the housing and over angular wall 62, and thence upwardly through outlet opening 37. This elongated and circuitous path effects a retention of the effluent in the afterburner chamber for a sufliciently long period of time to assure a complete combustion thereof. In addition, the sharp 180 turns assure a turbulent and thorough mixing of the air and eflluent providing improved efltciency in the combustion. Still further, as the flow passage extends horizontally, deposit of fly ash does not block any one portion thereof, but rather any such fly ash is deposited over the substantial length of the passage, substantially minimizing cleaning maintenance of the afterburner.

In the illustrated embodiment, burner 18 comprises a power burner providing approximately 24,000 B.t.u.s per hour. It should be understood that, within the scope of the invention, burners 16 and 18 may comprise other suitable burner means, such as electrically operated burners, and may provide other suitable amounts of heat energy. However, burner 18 must be capable of raising the temperature within afterburner chamber 15 to a sufiicient degree to assure a proper completion of the combustion therein. It has been found that the minimum temperature for this purpose is approximately 1300 F.

The instant invention comprehends an improved air delivery to the ignition and afterburner chambers, effecting an automatic regulation of the combustion therein. As indicated above, the combustion air is preheated by its passage against afterburner housing 14 prior to delivery through lower open end 17 of the ignition chamber housing. Such heat transfer provides not only improved efficiency of combustion in ignition chamber 12 but also serves to reduce the outlet temperature of the effluent, which temperature reduction is highly desirable relative to fire hazard considerations. As indicated above, air is drawn into the afterburner chamber 15 through openings 31 as a result of the suction pressure induced in chamber 15 as the products of combustion pass from opening 35 into the space between wall 49 and side wall 50. Thus, a large rate of flow, as might result from the burning in chamber 12 of highly combustible material (such as dry paper or cardboard), efiects an increase in the amount of air drawn into chamber 15 to be mixed with the products of combustion. Alternatively, a low rate of flow, as might be caused by burning damp garbage in chamber 12, effects a decreased delivery of air. To preclude a reverse flow through openings 31 (of the combustion products entering the afterburner chamber), a baffle plate 64 is carried on wall 32 to extend angularly upwardly in front of openings 31 and deflect the flow away from the openings.

To assure proper operation of incinerator 10, it is desirable to provide only a limited amount of air to ignition chamber 12 so that only a partial combustion of garbage occurs therein, and permit completion of the combustion to occur in afterburner chamber 15. The control of the volume of air admitted through lower end 17 into ignition chamber 12 is efiiected by properly dimensioning the openings 65 in the member 11a between ignition chamber housing 11 and the outer enclosure 19 so that the openings 65 therebetween properly throttles the air delivery the requisite amount. Thus, the draft through the entire incinerator is controlled automatically by the damper 41 which admits more or less air into the space above angular wall 62 adjacent outlet opening 37 depending on the draft at the outlet opening 37, and the ratio of air volumes delivered to the ignition and afterburner chambers is controlled automatically by the co-ordinated functioning of the openings 65 and openings 31 which divert more or less air from openings 65 directly into afterburner chamber 15 depending on the draft adjacent inlet opening 35.

The operation of the incinerator 10 may be effected by suitable automatic control means such as disclosed in our Patent No. 3,104,629, issued September 24, 1963, which disclosure may be incorporated fully herein.

Briefly, however, the operation of incinerator may be controlled by a 24-hour timer 67 for daily automatic operation of the incinerator at selected times. Timer 67 in turn may control a suitable program timer 77 which controls the burners 16 and 18 concurrently with the above discussed control of the air flow through the incinerator to provide an improved combustion therein. Suitable thermostatic control means suoh as thermostat 113 (FIGURE 2) may be provided for controlling the operation of burner 16 and thermostat 117 (FIGURE 1) which controls operation of each of the burners. The incinerator may be provided with a signal light 100 for indicating an excess ash condition preventing proper operation of the incinerator.

While we have shown and described certain embodiments of our invention, it is to be understood that it is capable of many modifications. Changes, therefore, in the construction and arrangement may be made without departing from the spirit and scope of the invention as defined in the appended claims.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. An incinerator, comprising: means defining an ignition chamber having a boundary wall provided with an outlet opening; means defining an afterburner chamber for receiving products of combustion passed through said opening from the ignition chamber; a first burner in said ignition chamber; a second burner in said afterburner chamber spaced from said opening, said afterburner chamber means including means for conducting the products of combustion in a stream from said opening to said second burner; means providing in preselected ratios a first supply of air to said ignition chamber for supporting combustion therein, and a second different supply of air to said afterburner chamber for mixing with said products of combustion in said stream prior to the delivery thereof to said second burner for supporting further combustion in said afterburner chambers; and means for concurrently controlling said burners and the total quantity of air provided by said air providing means to said ignition chamber and afterburner chamber to adjust the operation of the incinerator for proper combustion of different materials having different combustion characteristics.

2. The incinerator in claim 1 wherein said air providing means includes a bafile in said afterburner chamber adjacent said opening arranged to direct both said second supply of air and said products of combustion away from said opening and toward said second burner.

3. The incinerator of claim 1 wherein said air providing means provides said air supplies in a substantially constant ratio.

4. The incinerator of claim 1 wherein said controlling means includes first fixed means for throttling the air delivery to said ignition chamber, second fixed means for throttling the air delivery to said afterburner chamber, and variable means for controlling the draft through the series related ignition chamber and afterburner chamber.

References Cited by the Examiner UNITED STATES PATENTS 1,137,232 4/1915 Rickets -18 1,281,488 10/1918 Best 110-8 1,528,816 3/1925 Cummings 110--8 1,995,723 3/1935 Van Denburg 110--8 2,549,517 4/1951 Persons 1108 X 2,610,682 9/1952 Weber. 2,628,677 2/1953 Strobel. 2,646,758 7/1953 Greeman. 2,711,139 6/1955 Martin. 2,752,870 7/1956 Short et al 110 -s X 2,879,862 3/1959 Burden. 2,988,023 6/ 1961 Osswald. 3,043,248 7/1962 Martin 110-8 FOREIGN PATENTS 141,160 4/1920 Great Britain.

FREDERICK L. MATT ESON, IR., Primary Examiner.

JAMES W. WESTHAVER, Examiner.

H. B, RAMEY, Assistant Examiner. 

1. AN INCINERATOR, COMPRISING: MEANS DEFINING AN IGNITION CHAMBER HAVING A BOUNDARY WALL PROVIDED WITH AN OUTLET OPENING; MEANS DEFINING AN AFTERBURNER CHAMBER FOR RECEIVING PRODUCTS OF COMBUSTION PASSED THROUGH SAID OPENING FROM THE IGNITION CHAMBER; A FIRST BURNER IN SAID IGNITION CHAMBER; A SECOND BURNER IN SAID AFTERBURNER CHAMBER SPACED FROM SAID OPENING, SAID AFTERBURNER CHAMNER MEANS INCLUDING MEANS FOR CONDUCTING THE PRODUCTS OF COMBUSTION IN A STREAM FROM SAID OPENING TO SAID SECOND BURNER; MEANS PROVIDING IN PRESELECTED RATIOS A FIRST SUPPLY OF AIR TO SAID IGNITION CHAMBER FOR SUPPORTING COMBUSTION THEREIN, AND A SECOND DIFFERENT SUPPLY OF AIR TO SAID AFTERBURNER CHAMBER FOR MIXING WITH SAID PRODUCTS OF COMBUSTION IN SAID STREAM PRIOR TO THE DELIVERY THEREOF TO SAID SECOND BURNER FOF SUPPORTING FURTHER COMBUSTION IN SAID AFTERBURNER CHAMBERS; AND MEANS FOR CONCURRENTLY CONTROLLING SAID BURNERS AND THE TOTAL QUANTITY OF AIR PROVIDED BY SAID AIR PROVIDING MEANS TO SAID IGNITION CHAMBER AND AFTERBURNER CHAMBER TO ADJUST THE OPERATION OF THE INCINERATOR FOR PROPER COMBUSTION OF DIFFERENT MATERIALS HAVING DIFFERENT COMBUSTION CHARACTERISTICS. 